Automatic motor driven reversible closure operator

ABSTRACT

An overhead control for raising and lowering garage doors and other cyclically operated devices which utilizes a unidirectional electric motor which drives an endless chain in only one direction. A follower rides on a rail and is coupled to the endless chain by a gear which engages the chain on one side so as to move the follower in a first direction. When the follower reaches the end of the rail, the gear of the follower rotates 180* so as to engage the opposite side of the chain and thus move the follower in the opposite direction. The tension may be adjusted so that a door will stop or reverse when it meets resistance sufficiently firm to shift the gear of the follower.

United States Patent Purtilo AUTOMATIC MOTOR DRIVEN REVERSIBLE CLOSUREOPERATOR Dennis L. Purtilo, Waterloo, Iowa Chamberlain ManufacturingCorporation, Waterloo, Iowa Filed: Aug. 26, 1971 Appl. No.: 175,046

Inventor:

Assignee:

US. Cl. ..3l8/475, 318/266, 318/267, 318/467, 49/28 Int. Cl. ..1-l02pl/00 Field of Search ..318/475, 266, 267, 318/467; 49/28 ReferencesCited UNITED STATES PATENTS 9/1958 Klamp t ..3l8/475 X 2,752,150 6/1956Richmond et a1. ..318/415 X Primary Examiner-T. E. Lynch AttorneyCarltonl-Iill-et a1.

[5 7] ABSTRACT An overhead control for raising and lowering garage doorsand other cyclically operated devices which utilizes a unidirectionalelectric motor which drives an endless chain in only one direction. Afollower rides on a rail and is coupled to the endless chain by a gearwhich engages the chain on one side so as to move the follower in afirst direction. When the follower reaches the end of the rail, the gearof the follower rotates 180 so as to engage the opposite side of thechain and thus move the follower in the opposite direction. The tensionmay be adjusted so that a door will stop or reverse when it meetsresistance sufficiently firm to shift the gear of the follower.

16 Claims, 8 Drawing Figures PATENTEI] APR 1 7 I973 SHEET 2 [IF 3 vJNVENTOR.

. Dav/W3 Z uerma I @WA'ITORNEYS A AUTOMATIC MOTOR DRIVEN REVERSIBLECLOSURE OPERATOR BACKGROUND OF THE INVENTION 1. Field of the InventionThis invention relates in general to door controls and particularly toremotely controlled electrically operated overhead door operators.

2. Description of the Prior Art Overhead door controls which lower andraise the door between the opened and closed positions have been used inthe past but they generally depend upon a reversible electric motor fortheir operation which runs in a first direction to close the door and ina second direction to open the door. Reversible electric motors areexpensive and require relatively expensive control systems and thus themaintenance of the unit is greater than that of a unidirectional motor.Also some of the controls do not provide safety features to prevent themotor from burning out and damage to the components, or, even possiblepersonal injury which may occur in case the door or mechanism isobstructed or other malfunction.

SUMMARY OF THE INVENTION The purpose of the present invention is toprovide anoverhead door control which is powered by a unidirectionalelectric motor which drives a chain and which includes a followercoupled to the door such that the follower is driven in a firstdirection by the chain to close the door and in a second direction toopen the door. The follower includes a gear with teeth such that thegear is driven to move the follower in a first direction with the gearin a first orientation until the gear reaches the end of travel orencounters an obstruction at which time the gear rotates 180 and engagesthe other side of the chain and is moved in the opposite direction bythe chain. The invention provides a safety feature to prevent damage tocomponents or possibl personal injury in case the door encounters anobstruction or other mechanical malfunction occurs. Also, the forcerequired to reverse the direction of the mechanism may be adjusted tosuit the particular conditions of the situation.

This invention is applicable to any cyclically operated device and isnot to be limited to overhead doors although they serve as an example ofthe invention.

Means are provided for locking the gear in a position so that it travelsaway from the end of the track thus assuring that ice or otherobstructions will be broken as the door starts to open or close.

Other objects, features and advantages of the invention will be readilyapparent from the following description of certain preferred embodimentsthereof taken in conjunction with the accompanying drawings althoughvariations and modifications may be effected without departing from thespirit and scope of the novel concepts of the disclosure, and in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of the garagedoor operator of this invention;

FIG. 2 is a side view of the garage door opener illustrating the garagedoor engaging an obstruction;

FIG. 3 illustrates the garage door opener of this invention engaging anobstruction;

FIG. 4 is a top plan view illustrating the garage door operator of theinvention;

FIG. 5 is an enlarged sectional view taken on line V-V of FIG. 4;

FIG. 6 is an enlarged exploded view of the follower and gear mechanismof the invention;

FIG. 7 is a perspective view of one end of the guide rail; and

FIG. 8 is an electrical schematic view of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a side viewillustrating a garage door 11 in the closed position and a garage dooroperator is mounted between the headwall 10 adjacent the door and asuitable support at the other end thereof and includes a rail 21 onwhich a follower block mechanism 12 is mounted and driven by a chain 16that passes over sprockets 18 and 19 mounted at either end of the rail21. A follower arm 13 is attached by bracket 14 to the door 11 {and asimilar bracket to follower 12 such that as the follower 12 moves backand forth on the rail 21 relative to FIG. 1 the door 11 may be raisedand lowered.; It is to be realized, of course, that the pivot mechanismsfor the door are not shown since such mechanisms are conventional andare well known to those skilled in the art.

FIGS. 4 through 7 illustrate the follower and track mechaniam in greaterdetail. For example, FIG. 4 is a top view illustrating the gears 18 and19 rotatably mounted on suitable shafts 24 and 26, respectively, withthe chain 16 extending over the gears. A motor 140 in FIG. 8 is mountedin housing 23 and has an output shaft 24 which carries the gear 18.Housing 22 is mounted adjacent the headwall 10 and rotatably supportsthe shaft 26 which carries the gear 19. The follower 12 is formed with acentral groove 42 in which the raised portion 33 of the rail 21 isreceived. The follower 12 has a gear 47 mounted thereon with five teeth48, 49, 50, 51 and 52 which sequentially engage the chain 16. The drivetooth 50 is made of electrical con ducting material as for example metaland the teeth 48, 49, 51 and 52 are electrically insulated from the gear47. All gear teeth may be of the same material and a protrusion 141 maybe added to the side of the gear 47 to contact the contact 74. As bestshown in FIG. 6, the gear 47 fits into an opening 44 of the follower 41and over a shaft 46 which is non-rotatably mounted in the follower 41 inthe opening 43. An opening 53 is formed in the periphery of the gear 47on one side thereof for receiving overload pins 121 and 38. A pair ofclutch openings 56 and 57 are formed in the top surface relative to FIG.6 of the gear 47 and are adapted to receive clutch pin extensions 59 and61 which are mounted in a clutch plate 58 that bears against the surfaceof the gear 47. The clutch plate is formed with a central opening whichincludes a pair of keyways 64 and 66 in which keys 62 and 63 arereceived for non-rotatably locking the clutch plate to the shaft 46. Thekeys 62 and 63 are received in keyway 67 formed in the shaft 46 thuspreventing the clutch plate 58 from rotating relative thereto.

A clutch spring 68 fits over the shaft 46 between the clutch plate 58and a washer 69 and a nut 71 is threadedly received on a threadedportion 70 of the shaft 46 to hold the assembly together.

The upwardly extending portion 33 of the rail 21 has an electricallyconducting strip 34 attached to one side thereof which is contacted by awiper contact 73 of a brush 72 insulatingly mounted on the follower 51.The brush 72 has an electrically contacting portion 74 which isengageable with the electrical conducting tooth 50 of the gear 47 whenthe gear 47 rotates as will be described hereafter. In other words, eachtime the gear 47 rotates so that the tooth 50 engages the wiper 74 ofthe brush 72, an electrical circuit will be completed from theconducting strip 34 to the electrically conducting rail 33 through thewiper 73, brush 72, tooth 50, gear 47, the follower body portion 41 andto rail 33. Normally the rail 33 is insulated from the conducting strip34 and the circuit is not completed through the satellite 47 As bestshown in FIG. 5, an opening 81 is formed in the groove 42 of thefollower 41 adjacent the strip 34 so that electrical contact is not madebetween the follower 41 and the strip 34 under normal conditions.

A spring-biased overload pin 38 is mounted in the end wall 36 of thesupport 22 as best shown in FIG. 7 and is aligned with an opening 119formed in the follower block 41. A similar overload pin 121 is mountedin the motor housing 23 at the opposite end of the rail 21 and isaligned with an opening 118 formed in the follower block 41. As bestshown in FIG. 7, a brush 37 has one end connected to the electricallyconducting strip 34 and has a portion for engaging the electricallyconductive tooth 50 to complete an electrical circuit between theelectrical conductor 34 and the rail 21.

As best shown in FIGS. 4 and 5, upwardly extending guide projections 82and 84 are mounted on one side of the follower block 41 by suitablebolts 83 and 86, respectively, so as to confine the chain 16 on the topof the follower block 41 so that it is engageable with the teeth 48-52of the gear 47. The other side of the follower block has a pair ofupwardly extending chain guides 87 and 89 which are mounted to the block41 by bolts 88 and 91, respectively.

In operation, assume that the motor which drives the drive shaft 24 andgear 18 starts to drive the gear 18 clockwise relative to FIG. 4 whenthe follower 12 is in the position shown in FIG. 4. At this time the pin38 extends into the aligned opening of the block 41 and its end isreceived in the overload locking opening 53 of the gear 47. This assuresthat as the chain starts to move it will exert transverse force on thedrive tooth 50 of the gear 47 thus moving the actuating mechanism 12 tothe right relative to FIG. 4. As soon as the block 41 moves so that thelocking pin 38 is out of the aligned opening 53 of the gear 47, the gearis no longer locked by the pin from rotating relative to the block 41.However, the clutch plate 58 is locked to the shaft 46 and the clutchpins 59 and 61 are pushed by the spring 68 into the clutch openings 56and 57 of the gear 47 which will allow the gear 47 to drive the block 41as the chain 16 moves. The drive mechanism 12 will move on the track 21until the surface 35 of the housing 23 is engaged by the block 41 whichlimits its motion to the right relative to the figure. The overload pin121 will move into the opening 118 of the block 41 but it will not lockthe gear 47 so that it cannot rotate because the locking opening 53 ison the opposite side of the gear 47 at that time and the pin 121 will bedepressed against its biasing spring by the gear 47. Since the block 41can move no farther to the right relative to the housing 23 since itbears against the face 35, the chain 16 will continue to move as shownby the arrow 'of FIG. 4 and the drive teeth 48-52 will rotate the gear47 such that the drive tooth 50 engages the opposite side of the chain16 so that the follower mechanism 12 will be driven to the left relativeto FIG. 4. It is to be realized that the gear 47 has one tooth missing;this tooth is missing at the position of the gear opposite the positionof the drive tooth 50 such that when the drive tooth 50 engages thechain 16 the gear will be driven by the side of the chain which isengaged by the tooth 50 and the opposite side of the chain will slip inthe opposite direction past the gear since no tooth is present at thatposition.

The clutch plate 58 and clutch pins 59 and 61 lock the gear 47 in one oftwo positions spaced 180 apart which positions cause the followermechanism to be driven to the left or right relative to FIG. 4 dependingupon the position of tooth 50. The tension for overcoming the clutchspring is adjustable with the nut 71 so that the tighter the spring 68is compressed the more force will be required to move the gear throughth 180 shifting position.

FIG. 8 is an electrical schematic for the invention and comprises atransmitter 127 which has an antenna 129 and an energizing button 128.Thus to actuate the garage door opener the button 128 is depressed thusradiating a signal which is received by a receiver 103 having an antenna131 to actuate a self-holding relay 104. The receiver 103 is connectedto power lines 101 and 102 and the relay 104 momentarily closes theswitch S1 which has a holding coil 106 connected to power line 101. Theswitch S1 completes the circuit to the motor through leads 107, switchS2 which is normally held closed by spring 111, lead 108 and lead 109.Thus, when the receiver produces an output to energize the relay 104 andmomentarily closes switch S1 the holding coil 106 holds the switch S1 inthe closed position and the motor 140 starts to run. Since the motor isa unidirectional motor it always runs in the same direction thus drivingits output shaft 24 and the chain 16 through the drive gear 18. If thedoor operator mechanism 12 is assumed to be closed at the starting timeit will then move to the right relative to FIG. 8 opening the door ofthe garage. When the door actuator mechanism 12 of the invention movesto the right end of the rail relative to FIG. 8, the follower block 41will engage an electrical contact which completes the circuit betweenthe rail 21 and the conducting strip 34. A stop relay 98 has one sideconnected to the power terminal 102 and the other side connected to thestrip 34 and the contact 37 mounted at the rail 21. The rail 21 isconnected by lead 96 to the other power terminal 101. Thus when thefollower block 41 closes the circuit between strip 34 and the rail 33,the dropout relay 98 will be energized opening switch S2 against thespring 11 1, thus turning off power to the motor 140 which will stop.Simultaneously the switch S1 will drop out since its holding coil 106 isno longer energized through the switch S2. The contact 37 is mounted sothat it only momentarily engages the conductive tooth 50 to apply apulse to the dropout relay 98 and the follower block 41 does not makecontinuous contact between the rail 21 and the strip 34 when in the offposition at the ends of the rail.'In other words, the follower blockmerely momentarily closes the circuit between the rail 21 and the strip34 to pulse the drop-out relay 98 to turn off the motor but does nothold the drop-out relay energized. The switch S2 closes due to thespring 111 after the switch S1 is open.

Thus the garage door will have moved from the closed to the openedposition with the follower block 41 against the wall 35 of the housing23. As the motor 140 comes to a stop the gear 47 may commence orcompletely turn so that the driving tooth 50 moves from engagement withthe first side of the chain 16 to engagement with the second side beforethe motor 140 stops completely. On the other hand if the gear 47 has notcompletely moved from the first to the second locked position, it willcomplete such movement when the motor 140 is energized a second time.The motor is energized a second time by pulsing the transmitter 127 withthe button 128 or alternatively by manually depressing the push button126 to close the switch S3 which is connected through a holding coil 114and lead 112 to power lead 101. The opposite side of the switch S3 isconnected to the lead 107 through a lead 113. Closing switch S3completes the circuit to the motor 140 through the normally closedswitch S2 and the motor will start to run in the same direction asbefore. This will complete the rotation of the gear 47 if it had notbeen completely rotated such that the tooth 50 engages the second sideof the chain 16 and as the rotation is completed the locking pin 121will move into the opening 118 of the follower block 41 and into thelocking opening 53 of the gear so as to prevent it from moving until thefollower block moves to the left relative to FIG. 8 and the pin 121moves out of the opening 53.

The motor 140 will continue to run moving the garage door actuatingmechanism 12 to the left relative to FIGS. 4 and 8 until the garage dooris closed and the follower block 41 momentarily completes the circuitthrough wiper contact 37 from the strip 34 to the rail 21 thus pulsingthe drop-out relay 98 which opens switch S2 thus stopping the motor 140.The switch S3 will open since the holding coil 114 is de-energized whenthe switch S3 opens and the associated spring opens the switch contactS3.

Thus, each time the transmitter 127 is energized by depressing thebutton 128, the garage door will be actuated to move either from theclosed to the opened or from the opened to the closed position. Afterthe operation has been completed, the motor will be deenergized and thedoor will be in the commanded position. The commands may also be givenby the push button switch 126 which may be mounted in the garage tomanually operate the door.

When the electrically conducting tooth 50 engages the contact 74 of thebrush 72, an electrical circuit is completed between the strip 34 andthe rail 21 which pulses the drop-out relay 98. The purpose of thisswitch 6 is to cause the door operator to stop when it starts up andencounters an obstruction as illustrated in FIG. 3.

When the door 11 engages an obstruction 32 which prevents it fromraising further, the chain 16 will continue to move driving the gear 47to the reverse position such that the driving tooth 50 moves tomomentarily engage the contact 74 thus completing a circuit from therail 21 through the tooth 50, the contact 74, the brush 72 and thecontact 73 to the electrical conducting strip 34, thus causing thedrop-out relay 98 to be energized opening the switch S2 and causing themotor to stop. Thus the motor 140 will stop when an obstruction isencountered as the door is being opened because the gear completes anelectrical circuit to the drop-out relay 98 as the gear is driven from afirst to a second locked position.

Alternatively, if, as shown in FIG. 2, an obstruction 31 is encounteredas the door is being lowered from the opened to the closed position, themotor will not be stopped since the electrical conducting tooth 50 doesnot complete the circuit between the rail 21 and the electricalconducting strip 34 as the gear rotates because the tooth does notengage the contact and thus the motor will continue to run returning thedoor to the full up position before the motor is turned off byengagement of the follower'block 41 with the contact 74.

The locking pins 38 and 121 prevent the gear 47 from rotating at theinitiation of movement as for example when the door is slightly frozento the ground and greater than normal force is required to break thedoor from the ice. As soon as the door starts to move, the overload pinsmove out of engagement with the gear and the gear is free to rotate if aresisting force is encountered greater than that established by thesetting of the clutch spring 68 by the nut 71.

It is seen that this invention provides a simple and compact garage dooroperator and although it has been described with respect to preferredembodiments it is not to be so limited as changes and modifications maybe made which are within the full intent and scope as defined by theappended claims.

Iclaim:

1. An operator for a cyclically operated device comprising:

a rail mounted above said device;

a follower movable on said rail and connected to said device to controlits position;

an endless chain belt movably mounted with first and second sides ofsaid belt on opposite sides of said rail;

a unidirectional driving means connected to drive said endless belt inone direction; said follower formed with guides for slidably engagingsaid first and second sides of said belt,

gear engaging means comprising a gear rotatably mounted on said followerand having at least one tooth engageable alternatively with said firstand second sides of said belt, and clutch means mounted on said followerbetween said gear and said follower to prevent said gear from rotatingrelative to said follower unless a predetermined torque is applied tosaid gear by said belt.

2. An operator for a cyclically operated device according to claim 1wherein said guide means on said follower hold said belt in engagementwith said one tooth of said gear.

3. An operator for a cyclically operated device according to claim 1including a pair of stop means mounted at opposite ends of said rail andengageable with said follower to limit its motion.

4. An operator for a cyclically operated device according to claim 3wherein said gear has five teeth spaced about the surface of the gear at60 intervals and with a 120 gap formed between two of said teeth andsaid one tooth having teeth spaced at 60 and 120 on either side thereof.

5. An operator for a cyclically operated device according to claim 1wherein said gear has a depression and said clutch means includes aclutch plate nonrotatably mounted relative to said follower and saidclutch plate has a clutch pin receivable in said depression of saidgear.

6. An operator for a cyclically operated device according to claim 5further including a clutch spring engageable with said clutch plate tobias it toward said gear.

7. An operator for a cyclically operated device according to claim 6further including means for adjusting the spring tension on said clutchspring.

8. An operator for a cyclically operated device according to claim 4including a pair of overload pins each mounted on said stop means andsaid gear formed with an opening into which an overload pin may bereceived after said follower has engaged one of said stops and said gearhas rotated 180.

9. An operator for a cyclically operated device according to claim 8wherein said follower is formed with a pair of openings at opposite endswhich align with said overload pins and said opening in said gear intowhich said overload pins are received.

10. An operator for a cyclically operated device according to claim 9wherein said overload pins are flexibly mounted in said stop means formovement in said one and opposite directions.

11. An operator for a cyclically operated device according to claim 4comprising a control means including means for energizing saidunidirectional driving means, and first and second means forde-energizing said driving means mounted at opposite ends of said railand respectively actuated by said follower when it reaches either end ofsaid rail.

12. An operator for a cyclically operated device according to claim 11further including third means for de-energizing said driving means whensaid gear rotates intermediate the ends of said rail due to an overloadcondition.

13. An operator for a cyclically operated device according to claim 12wherein said driving means is an electrical motor and said first, secondand third deenergizing means includes electrical switches connected inparallel, a drop-out relay connected in circuit with said switches, anda stop switch connected in circuit with said electrical motor and saidstop switch controlled by said drop-out relay.

14. An operator for a cyclically operated device according to claim 13wherein a protrusion on said gear is engageable with said thirdde-energizing switch to actuate it.

15. An operator for a cyclically operated device according'to claim 14wherein said energizing means includes a remote controlled switchconnected in circuit with said electrical motor to energize it.

16. An operator for a cyclical y operated device according to claim 15including a radio transmitter and receiver for energizing said remotecontrolled switch.

1. An operator for a cyclically operated device comprising: a railmounted above said device; a follower movable on said rail and connectedto said device to control its position; an endless chain belt movablymounted with first and second sides of said belt on opposite sides ofsaid Rail; a unidirectional driving means connected to drive saidendless belt in one direction; said follower formed with guides forslidably engaging said first and second sides of said belt, gearengaging means comprising a gear rotatably mounted on said follower andhaving at least one tooth engageable alternatively with said first andsecond sides of said belt, and clutch means mounted on said followerbetween said gear and said follower to prevent said gear from rotatingrelative to said follower unless a predetermined torque is applied tosaid gear by said belt.
 2. An operator for a cyclically operated deviceaccording to claim 1 wherein said guide means on said follower hold saidbelt in engagement with said one tooth of said gear.
 3. An operator fora cyclically operated device according to claim 1 including a pair ofstop means mounted at opposite ends of said rail and engageable withsaid follower to limit its motion.
 4. An operator for a cyclicallyoperated device according to claim 3 wherein said gear has five teethspaced about the surface of the gear at 60* intervals and with a 120*gap formed between two of said teeth and said one tooth having teethspaced at 60* and 120* on either side thereof.
 5. An operator for acyclically operated device according to claim 1 wherein said gear has adepression and said clutch means includes a clutch plate non-rotatablymounted relative to said follower and said clutch plate has a clutch pinreceivable in said depression of said gear.
 6. An operator for acyclically operated device according to claim 5 further including aclutch spring engageable with said clutch plate to bias it toward saidgear.
 7. An operator for a cyclically operated device according to claim6 further including means for adjusting the spring tension on saidclutch spring.
 8. An operator for a cyclically operated device accordingto claim 4 including a pair of overload pins each mounted on said stopmeans and said gear formed with an opening into which an overload pinmay be received after said follower has engaged one of said stops andsaid gear has rotated 180*.
 9. An operator for a cyclically operateddevice according to claim 8 wherein said follower is formed with a pairof openings at opposite ends which align with said overload pins andsaid opening in said gear into which said overload pins are received.10. An operator for a cyclically operated device according to claim 9wherein said overload pins are flexibly mounted in said stop means formovement in said one and opposite directions.
 11. An operator for acyclically operated device according to claim 4 comprising a controlmeans including means for energizing said unidirectional driving means,and first and second means for de-energizing said driving means mountedat opposite ends of said rail and respectively actuated by said followerwhen it reaches either end of said rail.
 12. An operator for acyclically operated device according to claim 11 further including thirdmeans for de-energizing said driving means when said gear rotates 180*intermediate the ends of said rail due to an overload condition.
 13. Anoperator for a cyclically operated device according to claim 12 whereinsaid driving means is an electrical motor and said first, second andthird de-energizing means includes electrical switches connected inparallel, a drop-out relay connected in circuit with said switches, anda stop switch connected in circuit with said electrical motor and saidstop switch controlled by said drop-out relay.
 14. An operator for acyclically operated device according to claim 13 wherein a protrusion onsaid gear is engageable with said third de-energizing switch to actuateit.
 15. An operator for a cyclically operated device according to claim14 wherein said energizing means includes a remote controlled switchconnected in circuit with said electrical motor to energize it.
 16. AnoperaTor for a cyclically operated device according to claim 15including a radio transmitter and receiver for energizing said remotecontrolled switch.